On Mar 24, 2005, at 6:01 AM, C Smith <[EMAIL PROTECTED]> wrote:
What follows is an attempt based on the previous tutor-evolved sieve that extends the range in which to find the next prime by a factor of 2 over the last known prime. A similar algorithm is on ASPN (I bellieve), under
Space-efficient version of sieve of Eratosthenes. D. Eppstein, May 2004
Oh, please...ignore what I suggested and look at Eppstein's code. It's a thing of beauty and just keeps chugging out primes well past what the inefficient version that I suggested could do with the same memory. It's a "tortoise and hare" race as the memory gets chewed up by the esieve approach.
The ASPN version of Eppstein's program is an older one than the one at the following site: http://www.ics.uci.edu/~eppstein/PADS/Eratosthenes.py
How does one actually use this module? For example:
>>> import eratosthenes >>> eratosthenes.primes() <generator object at 0x640d0> >>> eratosthenes.primes().next() 2 >>> eratosthenes.primes().next() 2 >>> eratosthenes.primes().next() 2
How does one get beyond the first prime?
Thanks,
John
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